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OBJECTIVE: To determine the appropriate concentration of trypan blue (TB) for subretinal injection in a rat model and to provide a safety profile that limits retinal toxicity while maintaining dye visibility. MATERIALS AND METHODS: Adult rats were subretinally injected with various concentrations of either TB or phosphate-buffered saline (PBS); rats which received sham injections served as an additional control. The injected areas were visualized under a surgical microscope. Electroretinography (ERG) was performed to measure retinal function. Animals were then sacrificed, and the eyes were sectioned and examined by light microscopy. Terminal deoxynucleotidy1 transferase dUTP nickend labeling (TUNEL) was applied to determine retinal apoptosis. RESULTS: One day after the subretinal injection, TB stains were visible under the surgical microscope in the 0.2%, 0.08%, and 0.04% TB-injected groups, but not in the 0.02% TB-injected group. TB stain was detectable in the retina and sclera of the 0.2%, 0.08%, and 0.04% TB-injected groups for over 2 weeks after injection. However, the amplitudes of ERGa- and b-waves were affected and became significantly lower in the 0.2% TB-injected group than the amplitudes in the PBS-, or sham-injected group. Moreover, TUNEL+ cells appeared in the outer nuclear layer (ONL), ganglion cell layer (GCL), and retinal pigment epithelium (RPE) layer of the 0.2% and 0.08% TB-injected groups at 1 and 7 days after subretinal injection. In contrast, very few TUNEL+ cells were found in the 0.04% TB- or PBS-injected group. Two weeks after injection, the ONL was significantly thinner in the 0.2% TB-injected group than in the 0.04% TB-, PBS- or sham-injected group. CONCLUSIONS: TB injection induces a dose-dependent neurotoxic effect on retinal cells. Subretinal injection of 0.04% TB is relatively safe and effective for subretinal staining. [ABSTRACT FROM AUTHOR]

In this article, a realization version of quad-band filter is firstly proposed, and it is the cascaded structure composed of the shunt open-circuit DCRLH (dual composite right/left-handed) cell and the shunt short-circuit DCRLH cell. The above two cells are initially proposed here in order to improve the inherent limitations of the microstrip DCRLH cell. It is demonstrated that the matching performance and frequency selectivity of these two cells are both better than those of the microstrip DCRLH cell. It is more important that both the cells exhibit three transmission zeros within the given frequency band, and any of them is of great potential to be applied in the design of quad-band filters. In order to get sufficient design freedom, we utilize the cascade connection version based on the shunt open/short-circuit DCRLH cells. Whereas, only the first and second transmission zeros of both the shunt open/short-circuit DCRLH cells are explored. Both the simulated and measured results indicate that the proposed design method is right and effective. [ABSTRACT FROM AUTHOR]

Objective Thyrotoxic periodic paralysis (TTP) has been associated with genetic variations in the gene encoding the alpha 1 subunit of the L-type calcium channel (CACNA1S). Mutations in CACNA1S are known to account for the majority of cases of familial hypokalaemic periodic paralysis (HOKPP). In this study we have examined 48 genetic polymorphisms in the CACNA1S gene and genotyped a tagging set of representative polymorphisms to determine the role of this gene in TPP. Design and patients A genetic association study was carried out with 98 TPP patients and 162 male thyrotoxic controls. Among 47 polymorphisms evaluated for linkage disequilibrium (LD) and the spectrum of haplotypes in the Chinese population , 31 were selected as tagging single-nucleotide polymorphisms (SNPs) for genotyping the whole sample. A new genotyping protocol was used to analyse an insertion/deletion (I/D) polymorphism. Results We studied the LD among 47 polymorphisms in the CACNA1S gene, which comprised a set of high-density markers with an average of one SNP every 2 kb. Subsequently, 31 tagSNPs were genotyped for all the samples. The gene is composed of three LD blocks. With this block structure, we were confident that variations of the gene were comprehensively covered by the tagSNPs. No significant association was found between the polymorphisms and TPP. Conclusion We established the LD structure of this calcium channel subunit gene (CACNA1S) for the first time. However, its genetic variations are not associated with TPP in Chinese patients. [ABSTRACT FROM AUTHOR]

The modulatory effect of the protein kinase C activator was examined on contraction of rat isolated vas deferens induced by constrictive agonists, noradrenaline (NA), ATP, BaCl[sub 2] and high K[sup +] . Phorbol 12,13-diacetate (PDA, 1 μmol/l) induced a transient extracellular Ca[sup 2+] -dependent contraction while the inactive analogue, 4α-phorbol (1 μmol/l) had no effect. PDA significantly enhanced the peak amplitude of the contractile response to NA (0.1–10 μmol/l), ATP (100 μmol/l), Ba[sup 2+] (3 mmol/l) or high K[sup +] (30 mmol/l). Staurosporine at 30 nmol/l reduced the enhancing effect of PDA on the agonist-induced contraction. NA (10 μmol/l) produced a phasic contraction followed by a sustained contraction, while ATP induced monophasic contraction. Pretreatment with nifedipine (10 nmol/l) had no effect on the phasic contraction induced by NA, but it significantly reduced ATP- or high K[sup +] -induced contraction. Staurosporine (30 nmol/l) alone attenuated the peak contractile response induced by NA or ATP but not by Ba[sup 2+] . NA produced a transient contraction in Ca[sup 2+] -free Krebs solution, and PDA (1 μmol/l) markedly enhanced this effect. These novel data indicate that activation of a protein kinase C-dependent mechanism not only affects contraction mediated by Ca[sup 2+] influx through voltage-sensitive Ca[sup 2+] channels, but also promotes intracellular Ca[sup 2+] release or intracellular Ca[sup 2+] -mediated contractile mechanism in rat vas deferens.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: To explore the safety and feasibility of indocyanine green (ICG) injection through accessory incision in laparoscopic right hemicolectomy. Methods: A descriptive case series study was carried out. Clinicopathological data of 29 patients with colon cancer undergoing right hemicolectomy at Department of General Surgery, Guangdong Provincial People's Hospital were retrospectively analyzed. All the patients received ICG injection through accessory incision at the beginning of operation. Results: Among 29 patients, 13 were male and 16 were female with a mean age of (60.8±7.7) years and mean body mass index of (24.3±2.8) kg/m(2); 3 were stage I, 19 were stage II, 7 were stage III. Pericolic, intermediate and main lymph nodes could be detected under near infrared fluorescence imaging (NIRFI) in all the cases. No.6 lymph nodes were observed in 3 cases, while no lymph nodes around superior mesenteric vein (SMV) were found. The average number of fluorescent lymph node was 14.2±6.1. The average developing time of fluorescence was (36.2±3.7) minutes. The average number of harvested lymph nodes was 22.4±8.2. There was no extravasation of imaging agent during the operation, and there were no intraoperative complications such as allergies, massive abdominal bleeding, peripheral organ damage, etc. Operative time was (113.1±10.7) minutes, blood loss during operation was (22.4±3.9) ml, ambulatory time was (1.2±0.4) days, time to the first flatus was (1.7±0.7) days, time to the first fluid diet was (0.7±0.4) days, and postoperative hospital stay was (5.8±1.5) days. No operation-associated complications such as anastomotic bleeding, anastomotic leakage, peritoneal bleeding, peritoneal infection, incision infection occurred after operation. Conclusion: ICG injection through accessory incision in laparoscopic right hemicolectomy is safe and feasible.

Objective: To understand the current practice of preoperative bowel preparation in elective colorectal surgery in China. Methods: A cross-sectional questionnaire survey was conducted through wechat. The content of the questionnaire survey included professional title of the participants, the hospital class, dietary preparation and protocol, oral laxatives and specific types, oral antibiotics, gastric intubation, and mechanical enema before elective colorectal surgery. A stratified analysis based on hospital class was conducted to understand their current practice of preoperative bowel preparation in elective colorectal surgery. Result: A total of 600 questionnaires were issued, and 516 (86.00%) questionnaires of participants from different hospitals, engaged in colorectal surgery or general surgeons were recovered, of which 366 were from tertiary hospitals (70.93%) and 150 from secondary hospitals (29.07%). For diet preparation, the proportions of right hemicolic, left hemicolic and rectal surgery were 81.59% (421/516), 84.88% (438/516) and 84.88% (438/516) respectively. The average time of preoperative dietary preparation was 2.03 days. The study showed that 85.85% (443/516) of surgeons chose oral laxatives for bowel preparation in all colorectal surgery, while only 4.26% (22/516) of surgeons did not choose oral laxatives. For mechanical enema, the proportions of right hemicolic, left hemicolic and rectal surgery were 19.19% (99/516), 30.04% (155/516) and 32.75% (169/516) respectively. Preoperative oral antibiotics was used by 34.69% (179/516) of the respondents. 94.38% (487/516) of participants were satisfied with bowel preparation, and 55.43% (286/516) of participants believed that preoperative bowel preparation was well tolerated. In terms of preoperative oral laxatives, there was no statistically significant difference between different levels of hospitals [secondary hospitals vs. tertiary hospitals: 90.00% (135/150) vs. 84.15% (308/366), χ(2)=2.995, P =0.084]. Compared with the tertiary hospitals, the surgeons in the secondary hospitals accounted for higher proportions in diet preparation [87.33% (131/150) vs. 76.78% (281/366), χ(2)=7.369, P =0.007], gastric intubation [54.00% (81/150) vs. 36.33% (133/366), χ(2)=13.672, P <0.001], preoperative oral antibiotics [58.67% (88/150) vs. 24.86% (91/366), χ(2)=12.259, P <0.001] and enema [28.67% (43/150) vs. 15.30% (56/366), χ(2)=53.661, P <0.001]. Conclusion: Although the preoperative bowel preparation practice in elective colorectal surgery for most of surgeons in China is basically the same as the current international protocol, the proportions of mechanical enema and gastric intubation before surgery are still relatively high.

Objective: To analyze the pathogens of lower respiratory tract infection(LRTI) including bacterial, viral and mixed infection, and to establish a discriminant model based on clinical features in order to predict the pathogens. Methods: A total of 243 hospitalized patients with lower respiratory tract infections were enrolled in Fujian Provincial Hospital from April 2012 to September 2015. The clinical data and airway (sputum and/or bronchoalveolar lavage) samples were collected. Microbes were identified by traditional culture (for bacteria), loop-mediated isothermal amplification(LAMP) and gene sequencing (for bacteria and atypical pathogen), or Real-time quantitative polymerase chain reaction (Real-time PCR)for viruses. Finally, a discriminant model was established by using the discriminant analysis methods to help to predict bacterial, viral and mixed infections. Results: Pathogens were detected in 53.9% (131/243) of the 243 cases.Bacteria accounted for 23.5%(57/243, of which 17 cases with the virus, 1 case with Mycoplasma pneumoniae and virus), mainly Pseudomonas Aeruginosa and Klebsiella Pneumonia. Atypical pathogens for 4.9% (12/243, of which 3 cases with the virus, 1 case of bacteria and viruses), all were mycoplasma pneumonia. Viruses for 34.6% (84/243, of which 17 cases of bacteria, 3 cases with Mycoplasma pneumoniae, 1 case with Mycoplasma pneumoniae and bacteria) of the cases, mainly Influenza A virus and Human Cytomegalovirus, and other virus like adenovirus, human parainfluenza virus, respiratory syncytial virus, human metapneumovirus, human boca virus were also detected fewly. Seven parameters including mental status, using antibiotics prior to admission, complications, abnormal breath sounds, neutrophil alkaline phosphatase (NAP) score, pneumonia severity index (PSI) score and CRUB-65 score were enrolled after univariate analysis, and discriminant analysis was used to establish the discriminant model by applying the identified pathogens as the dependent variable. The total positive predictive value was 64.7%(77/119), with 66.7% for bacterial infection, 78.0% for viral infection and 33.3% for the mixed infection. Conclusions: The mostly detected pathogens were Pseudomonas aeruginosa, atypitcal pathogens, Klebsiella pneumoniae, influenza A virus and human cytomegalovirus in hospitalized patients with LRTI in this hospital. The discriminant diagnostic model established by clinical features may contribute to predict the pathogens of LRTI.

1. Endothelial cells have a key role in the cardiovascular system. Most endothelial cell functions depend on changes in cytosolic Ca(2+) concentrations ([Ca(2+)](i)) to some extent and Ca2+ signalling acts to link external stimuli with the synthesis and release of regulatory factors in endothelial cells. The [Ca(2+)](i) is maintained by a well-balanced Ca(2+) flux across the endoplasmic reticulum and plasma membrane. 2. Cyclic nucleotides, such as cAMP and cGMP, are very important second messengers. The cyclic nucleotides can affect [Ca(2+)](i) directly or indirectly (via the actions of protein kinase (PK) A or PKG-mediated phosphorylation) by regulating Ca(2+) mobilization and Ca(2+) influx. Fine-tuning of [Ca(2+)](i) is also fundamental to protect endothelial cells against damaged caused by the excessive accumulation of Ca(2+). 3. Therapeutic agents that control cAMP and cGMP levels have been used to treat various cardiovascular diseases. 4. The aim of the present review is to discuss: (i) the functions of endothelial cells; (ii) the importance of [Ca(2+)](i) in endothelial cells; (iii) the impact of excessive [Ca(2+)](i) in endothelial cells; and (iv) the balanced control of [Ca(2+)](i) in endothelial cells via involvement of cyclic nucleotides (cAMP and cGMP) and their general effectors.

Urocortin is a potent vasodilator, which plays physiological or pathophysiological roles in systemic circulation. However, little is known about its action on pulmonary circulation. The present study was aimed to characterize some cellular mechanisms underlying the relaxant effect of urocortin in isolated rat pulmonary arteries. Changes in isometric tension were measured on small vessel myographs. Urocortin inhibited U46619-induced contraction with reduction of the maximal response. Urocortin-induced relaxation was independent of the presence of endothelium. Inhibitors of nitric oxide (NO)-dependent dilator, NG-nitro-L-arginine methyl ester or 1H-[1,2,4]oxadizolo[4,3-a]quinoxalin-1-one, did not affect the relaxation. Astressin (100-500 nM), a corticotropin-releasing factor (CRF) receptor antagonist and KT5720, a protein kinase A (PKA) inhibitor reduced urocortin-induced relaxation. Urocortin produced less relaxant effect in 30 mM K+- than U46619-contracted arterial rings. Urocortin did not reduce CaCl2-induced contraction in 60 mM K+-containing solution. Ba2+ (100-500 microM) but not other K+ channel blockers reduced the relaxant responses to urocortin. Urocortin also relaxed the rings preconstricted by phorbol 12,13-diacetae in normal Krebs solution while this relaxation was less in a Ca2+-free solution. Our results show that urocortin relaxed rat pulmonary arteries via CRF receptor-mediated and PKA-dependent but endothelium/NO or voltage-gated Ca2+ channel-independent mechanisms. Stimulation of Ba2+-sensitive K+ channel may contribute to urocortin-induced relaxation. Finally, urocortin relaxed pulmonary arteries partly via inhibition of a PKC-dependent contractile mechanism., (Copyright 2004 Elsevier B.V.)

Berberine, is an alkaloid from Hydrastis canadensis L., Chinese herb Huanglian, and many other plants. It is widely used in traditional Chinese medicine as an antimicrobial in the treatment of dysentery and infectious diarrhea. This manuscript describes cardiovascular effects of berberine and its derivatives, tetrahydroberberine and 8-oxoberberine. Berberine has positive inotropic, negative chronotropic, antiarrhythmic, and vasodilator properties. Both derivatives of berberine have antiarrhythmic activity. Some cardiovascular effects of berberine and its derivatives are attributed to the blockade of K+ channels (delayed rectifier and K(ATP)) and stimulation of Na+ -Ca(2+) exchanger. Berberine has been shown to prolong the duration of ventricular action potential. Its vasodilator activity has been attributed to multiple cellular mechanisms. The cardiovascular effects of berberine suggest its possible clinical usefulness in the treatment of arrhythmias and/or heart failure.

The modulatory effect of the protein kinase C activator was examined on contraction of rat isolated vas deferens induced by constrictive agonists, noradrenaline (NA), ATP, BaCl2 and high K+. Phorbol 12,13-diacetate (PDA, 1 micromol/l) induced a transient extracellular Ca(2+)-dependent contraction while the inactive analogue, 4alpha-phorbol (1 micromol/l) had no effect. PDA significantly enhanced the peak amplitude of the contractile response to NA (0.1-10 micromol/l), ATP (100 micromol/l), Ba2+ (3 mmol/l) or high K+ (30 mmol/l). Staurosporine at 30 nmol/l reduced the enhancing effect of PDA on the agonist-induced contraction. NA (10 micromol/l) produced a phasic contraction followed by a sustained contraction, while ATP induced monophasic contraction. Pretreatment with nifedipine (10 nmol/l) had no effect on the phasic contraction induced by NA, but it significantly reduced ATP- or high K(+)-induced contraction. Staurosporine (30 nmol/l) alone attenuated the peak contractile response induced by NA or ATP but not by Ba2+. NA produced a transient contraction in Ca(2+)-free Krebs solution, and PDA (1 micromol/l) markedly enhanced this effect. These novel data indicate that activation of a protein kinase C-dependent mechanism not only affects contraction mediated by Ca2+ influx through voltage-sensitive Ca2+ channels, but also promotes intracellular Ca2+ release or intracellular Ca(2+)-mediated contractile mechanism in rat vas deferens., (Copyright 2001 S. Karger AG, Basel)

Aim: To examine the role of endothelium in the vascular responses to flavonoids, baicalein, baicalin, cardamonin, alpinetin, and to purified jasmine green tea (-)epicatechin in the isolated rate mesenteric artery rings., Methods: The isometric contraction was measured by Grass force-displacement transducers., Results: Both baicalein and baicalin enhanced the phenylephrine-induced contractile response in the endothelium-intact rings. This enhancement was abolished by pretreatment with the nitric oxide inhibitor NG-nitro-L-arginine or in the absence of the endothelium. Both flavonoids also inhibited the acetylcholine-induced endothelial nitric oxide-dependent relaxation. In contrast, cardamonin, alpinetin or (-)epicatechin induced both endothelium-dependent and -independent relaxation. NG-nitro-L-arginine meyhyl ester or endothelium denudation attenuated the endothelium-dependent relaxation to the same extent., Conclusion: Baicalein and baicalin enhanced the phenylephrine-induced contraction most likely through inhibiting production or/and release of endothelial nitric oxide. Whilst, cardamonin-, alpinetin- or (-)epicatechin-induced endothelium-dependent relaxation is primarily mediated through endothelial nitric oxide.

Aim: The present study was aimed to examine the vasorelaxant and antiproliferative responses to purified green tea epicatechin mixture, (-)epicatechin and (-)epigallocatechin gallate on rat arterial smooth muscle cells., Methods: Changes in isometric force were measured by Grass force transducer and effects on cell proliferation were evaluated using [3H]thymidine incorporation assay., Results: Epicatechin mixture, (-)epicatechin and (-)epigallocatechin gallate, which we isolated and purified from jasmine green tea, concentration-dependently, reduced the contractile response to phenylephrine in rat isolated aortic rings with (-)epigallocatechin gallate being more effective. These three agents also inhibited [3H]thymidine incorporation into DNA in cultured rat aortic smooth muscle cells in a concentration-dependent manner., Conclusion: The purified epicatechin derivatives from jasmine green tea relaxed the isolated rat arteries preconstricted by phenylephrine and inhibited aortic smooth muscle cell proliferation.

Quaternary ammonium ions are common pharmacological probes used to study the kinetic properties of K+ channels in smooth muscle cells. On the other hand, some ammonium compounds cause vasorelaxation through unknown mechanisms. The main aim of this study was to examine a unique role of endothelium in the vascular response to tetraoctylammonium ions (TOA+) in the isolated rat aorta. Changes in contractile force were measured by force transducers and total tissue content of cGMP was measured by radioimmunoassay. Endothelial cytosolic Ca2+ ([Ca2+]i) was assessed by laser scanning confocal microscopy.

The present study investigated the involvement of endothelial nitric oxide in relaxation induced by purified green tea (-)epicatechin in rat isolated mesenteric arteries. (-)Epicatechin caused both endothelium-dependent and -independent relaxation. NG-Nitro-L-arginine methyl ester (L-NAME, 100 microM) and methylene blue (10 microM) significantly attenuated (-)epicatechin-induced relaxation in endothelium-intact tissues. L-Arginine (1 mM) partially antagonized the effect of L-NAME. (-)Epicatechin-induced relaxation was inhibited by Rp-guanosine 3',5'-cyclic monophosphothioate triethylamine. In contrast, indomethacin and glibenclamide had no effect. (-)Epicatechin (100 microM) significantly increased the tissue content of cyclic GMP and NG-nitro-L-arginine (100 microM) or removal of the endothelium abolished this increase. (-)Epicatechin (100 microM) induced an increase in intracellular Ca2+ levels in cultured human umbilical vein endothelial cells. Iberiotoxin at 100 nM attenuated (-)epicatechin-induced relaxation in endothelium-intact arteries and this effect was absent in the presence of 100 microM L-NAME. In summary, (-)epicatechin-induced endothelium-dependent relaxation is primarily mediated by nitric oxide and partially through nitric oxide-dependent activation of iberiotoxin-sensitive K+ channels. In addition, there may be a causal link between increased Ca2+ levels and nitric oxide release in response to (-)epicatechin.

The endothelium-dependent and -independent relaxant effect of procaine was examined in isolated rat aortic rings. Procaine induced relaxation of arteries precontracted with phenylephrine or with 60 mM K+ in a concentration-dependent manner (0.01-3 mM). Procaine (1 mM) inhibited the transient contraction induced by caffeine (10 mM) in Ca2+-free Krebs solution. Removal of the endothelium caused a rightward shift of the concentration-response curve for procaine. N(G)-Nitro-L-arginine (L-NNA, 10-100 microM), N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM) and methylene blue (1-10 microM) significantly attenuated the procaine-induced relaxation without affecting the maximal response. L-Arginine (1 mM) partially but significantly antagonized the effect of L-NAME (100 microM). Pretreatment of endothelium-intact aortic rings with procaine (1 mM) or with acetylcholine (10 microM) significantly elevated the tissue contents of cyclic GMP and this increase was inhibited in the presence of 100 microM L-NNA. Tetrapentylammonium ions (1-3 microM) reduced the procaine-induced relaxation in both endothelium-intact and -denuded arteries. Tetrapentylammonium ions (3 microM) did not affect the procaine-induced relaxation of 60 mM K+-contracted arteries. Tetraethylammonium ions (3 mM) inhibited the procaine-induced relaxation. In contrast, iberiotoxin (100 nM), glibenclamide (3 microM), 4-aminopyridine (3 mM) and indomethacin (10 microM) had no effect. These results indicate that the procaine-induced relaxation may be mediated through multiple mechanisms. A substantial portion of the procaine-induced relaxation in rat aorta was caused by nitric oxide but not by other endothelium-derived factors. The activation of tetrapentylammonium- and tetraethylammonium-sensitive K+ channels contributes in part to the procaine-induced vasorelaxation. Besides, procaine may directly inhibit both external Ca2+ entry and internal Ca2+ release in aortic smooth muscle cells.

Previous studies have suggested that epididymal and sperm functions are subject to control by a local renin-angiotensin II system (RAS) in the rat epididymis. Type-1 angiotensin II receptor, AT1 and type-2 receptor, AT2 were localized in epididymal epithelium, indicating that RAS may act in a paracrine or autocrine fashion to regulate fluid secretion, probably through the basally placed membrane-bound AT1 protein as revealed by immunocytochemical and electrophysiological studies. In the present work, the expression of the angiotensin II receptor subtypes in the rat epididymis was showed by western blot analysis and reverse-transcription polymerase chain reaction (RT-PCR) using specific primers for the angiotensin II receptor subtypes. Western blot analysis showed the expression of AT1 receptor in the rat epididymis. Results from RT-PCR, using specific primers based on the corresponding angiotensin II receptor subtype genes for AT1a, AT1b and AT2 , demonstrated the differential expression of mRNAs from these receptor subtypes in the epididymides of mature and immature rats. Both the genes for AT1a and AT1b, but not that for AT2, are predominantly expressed in the epididymides of mature rat. In contrast, only AT1a and AT2 were highly expressed in the epididymides of immature rat. These results suggest that the expression of type-1 and type-2 angiotensin II receptor subtypes are developmentally regulated. Type-1 subtype may play a role in regulation of electrolyte and fluid transport in mature rat whereas type-2 subtype may be important in growth and development in the immature rat.